Easton Sonic 6.0 400 spine Carbon Arrows - 6 Pack - Go fast or go heavy! The Easton Sonic 6.0 is a 6mm high-performance hunting arrow engineered with high-performance speed and hunting accuracy in mind. The Sonic 6.0 is built from scratch in the USA using Easton's seamless Acu-Carbon process for 100% weight and spine consistency from shaft to shaft and from dozen to dozen. Lighter overall mass weight also provides for a wider-range of arrow build options; from light-weight speed setups to high-FOC/high-momentum heavyweights. 6mm ST Inserts included (18 grains) 6mm reduced-diameter higher-velocity 100% carbon-fiber construction Factory helical fletched with 2in Bully Vanes Pre-installed 6mm nocks Straightness +/- .003in Made in USA